Questions about UV and Ozone together

[Fersan]

Hello, I have been reading you for a few years, without writing anything here because of my bad English. Although learning a lot. Excuse my English; It's a mix of google translator and my own knowledge.
Here is my question: I have a 90 gallon aquarium with sump, live rock, skimmer (Deltec 1000i), and Sanders Certizon 100 (100mg/h) ozonator without air dryer, controlled by Profilux. The values so far for NO3 and PO4 have been 10 and 0.05, and the ORP was consistent at 300-420mv (cutoff point at 420mv). Nothing abnormal for me.
The thing is that, seeking to eradicate a slight outbreak of cyanobacteria and probable dinos, I have installed a 36w Jebao UV, with a flow of 260 gallons per hour.
After the installation of the UV I could see that the redox did not rise from 250-300mv. After several days, despite the fact that the ozonator was working all the time, it did not go up. The surprise was that this was accompanied by an increase in NO3 to 20!
I don't know what could be going on. On the one hand, I have read that UV destroys O3, I don't know if that is what has happened. For this reason, I do not know if it can be harmful if the ozonizer is working all the time without raising the Redox.
And I also have the question why the NO3 have risen. I do not know if the drop in Redox may have caused the rise in NO3 or if it was the installation of the UV. I would like to continue using ozone and UV together (UV for algae or disease and ozone to keep Redox around 350-400). I see better my aquarium in that range, although it can be subjective. Without ozone, the Redox stays consistent as a rock at 250mv.
I would appreciate your suggestions and input.
Greetings from the south of Spain.

 

[taricha]

Thanks for posting! (always impressed by those who can talk about this stuff in something other than their native language.)

Since UV sterilizers in fact do destroy ozone (O3 -> O2) and the ORP is reacting largely to the concentration of O3 in the tank, running the UV could be expected to lower ORP. ORP is mostly a measure of oxidizers and reducers in the water, not a measure of how "clean" the water is.
So I would first give up on your 350-400 ORP target, and cap the ozone input at something close to whatever level it was before you added UV.

The increased NO3 may indicate that organics that exists in tank water are being more rapidly broken down and oxidized to NO3 in the combined presence of UV and Ozone.

Some reading on combined UV and Ozone:
https://www.sciencedirect.com/science/article/pii/S0144860902000699

 

[Fersan]

Thanks, I'll read the link carefully.

 

[Fersan]

Anyone using UV and Ozone together? Is there any known problem with it?

 

[EugeneVan]

I am running UV 21 hrs/day and 7 days a week. The only time UV is off is when I dosing Amino acid to the tank. Also I am running an Ozonizer (28mg/h). It program to turn on every 4 hrs for 5 minutes in my 200 gal. I have been running this setup for over a year. I am very happy with the result. Water is crystal clear and I never experience any ugly stages.

 

[WVNed]

I ran both together an ended up with a very sterile tank. Nothing much to be seen at night when the lights were off.
I removed the UV and kept the ozone and things slowly returned to normal mostly.

 

[Randy Holmes-Farley]

Anyone using UV and Ozone together? Is there any known problem with it?

Im not convinced that is an issue because I think the ozone converts into other chemicals pretty fast.

A uv can kill bacteria, and dead bacteria may raise nitrate and lower ORP. Not sure if that’s it, but it’s possible.

 

[gbroadbridge]

Anyone using UV and Ozone together? Is there any known problem with it?

I use both together and causes no problems for me. The ozone runs overnight and the UV runs 24/7 unless dosing bacterial products at which time both are off for 4 hours.

ORP sits around 325.

 

[Viking_Reefing]

A uv can kill bacteria, and dead bacteria may raise nitrate and lower ORP. Not sure if that’s it, but it’s possible.

Yeah, that has been my experience. After implementing a UV unit the orp plummeted and stayed low for some time but eventually went back up.

 

[Fersan]

Thanks for the answers. My ORP has started to rise today. Perhaps also new plumbing and water flow has contributed to the drop in Redox. I will watch to see what happens with the nitrates in the days that follow. Greetings.

 

[Fersan]

I have increased the flow rate in the uv and the redox has dropped again. now it doesn't go above 240, being operating 24/7, any ideas? Could it be that UV destroys ozone by having a higher flow? Is there a risk of adding too much ozone, or if the redox does not rise is it ok? NO3 continue over 20 mg/l…

 

[Tommy e]

I don't think so or yes but maybe

 

[Andrew Schubert]

I ran across a video, where someone was running a UV on the outtake of their ozone reactor to remove the need of running carbon. Anyone seen an issue of this. I despise always changing carbon. So If this setup could work without carbon, seems like a win win to me.

 

[Randy Holmes-Farley]

I ran across a video, where someone was running a UV on the outtake of their ozone reactor to remove the need of running carbon. Anyone seen an issue of this. I despise always changing carbon. So If this setup could work without carbon, seems like a win win to me.

The question is wherever it is effective at removing ozone produced oxidants like bromate, not ozone itself.

Did the video author verify it was effective, and how?

I discuss the oxidant to toxicity here:

http://reefkeeping.com/issues/2006-03/rhf/index.php#15

 

[Andrew Schubert]

The question is wherever it is effective at removing ozone produced oxidants like bromate, not ozone itself.

Did the video author verify it was effective, and how?

I discuss the oxidant to toxicity here:

http://reefkeeping.com/issues/2006-03/rhf/index.php#15

Here is the video .... he talks about his setup of UV at the 16:50 mark.

 

[Superlightman]

I had put on in my new tank 1300-1400lbecause of algua issue ozon and an 25w eheim Uv in the sump wich is given for 2000l, unfortunately as I had many algua an a bacterial bloom the uv in the sump didn't to to much. So I put it directly on the main tank instead of the sump and add another uv jbl from 36w. So two uv same time. Well in one day water became clear and all Dino were gone. Second day all seemd well and coral had great polyp extension. Second day in the evening I did a small water change with a new salt for me as tropic Marin was not available, so I used dupla marin. Well in the morning all coral were close, zero polyp extensions, accropa all lost their colors or turned brown!
First I suspect the salt, but I not think it was the salt, probably two uv +ozon 24/7 make the water to aggressiv!
So I turned all of and they slowly recovery. Now I just turn on the uv 25w in the main tank, and it works without harm the coral. Placement of Uv is also important, but you can get to much of it so be careful, particularly in combination with ozon

 

[Superlightman]

I am running UV 21 hrs/day and 7 days a week. The only time UV is off is when I dosing Amino acid to the tank. Also I am running an Ozonizer (28mg/h). It program to turn on every 4 hrs for 5 minutes in my 200 gal. I have been running this setup for over a year. I am very happy with the result. Water is crystal clear and I never experience any ugly stages.

5 min only? How can this be effective in 5 min not a lot will pass through maybe you get same results without??

 

[Superlightman]

The question is wherever it is effective at removing ozone produced oxidants like bromate, not ozone itself.

Did the video author verify it was effective, and how?

I discuss the oxidant to toxicity here:

http://reefkeeping.com/issues/2006-03/rhf/index.php#15

Can uv +oxydator also produce bromate same as ozon?
When I use ozon my phosphate levels drops dramatically every time but not with the oxydator how can we explain this?

 

[Randy Holmes-Farley]

Can uv +oxydator also produce bromate same as ozon?
When I use ozon my phosphate levels drops dramatically every time but not with the oxydator how can we explain this?

The effects of hydrogen peroxide are very different than the much stronger oxidizer ozone. Hydrogen peroxide can act as a reducing agent on some elements, such as cupric copper and ferric iron.

FWIW, I am not sure why you would see a phosphate drop when using ozone.

 

[Superlightman]

The effects of hydrogen peroxide are very different than the much stronger oxidizer ozone. Hydrogen peroxide can act as a reducing agent on some elements, such as cupric copper and ferric iron.

FWIW, I am not sure why you would see a phosphate drop when using ozone.

I don't know where it comes but the phosphate drops happens every time I use ozone, I tried it multiple times, I'm very sure about it as I always struggle with high levels but every times I use ozone I drops fast, it is so effective that then I have to dose it. When I stop it phosphate increase